The invention relates to a link of a vehicle suspension and to a vehicle suspension including such a link.
Known vehicle suspensions include a number of components taking over the functions of guiding the corresponding wheel motion and storing energy introduced in the suspension because of the motion of the wheel.
In known vehicle suspensions, the functions of guiding the wheel motion and storing energy are often separated in several elements of the vehicle suspension. The consequence is a large number of elements bringing about high manufacturing costs, high mass, and sometimes packaging problems.
According to the invention, a link of a vehicle suspension is provided, the link being elastic and including three suspension points, a first point being adapted to be pivotally connected to a wheel carrier of the corresponding vehicle, a second point being adapted to be pivotally connected to a rigid chassis of the corresponding vehicle, and the third point being adapted to be pivotally connected to a shackle, the shackle pivotally connecting the third point to the rigid chassis.
According to the invention, a member of the suspension is replaced with a composite compliant member or link. The compliant or elastic member of the invention combines the functions of guiding the corresponding wheel and of elastically suspending the wheel. Thereby, the link may replace a guiding link and a conventional coil spring.
In a first preferred embodiment of the link, the link is an elongated leaf element, the first point being located at a first end of the elongated leaf element, the second point being located somewhere on the longitudinal extent of the elongated leaf element, and the third point being located at the second end of the elongated leaf element. This preferred link may replace a link element or control arm of known suspensions. In particular, the link according to the invention is used as an upper transverse or lateral control arm in an independent suspension of an automobile. Further, the link is advantageously used in a rear suspension of an automobile.
In a second preferred embodiment of the link, the first, second and third points each have a fixed position at the link. The fixed positions of the pivot points clearly define the degrees of freedom for guiding the wheel during its movement.
Further, according to the invention, a vehicle suspension is provided including at least one link, a wheel carrier, a rigid chassis and a shackle, the link being elastic and including three suspension points, a first point being pivotally connected to the wheel carrier, a second point being pivotally connected to the rigid chassis, and the third point being pivotally connected to the shackle, the shackle pivotally connecting the third point to the rigid chassis.
In a first preferred embodiment of the vehicle suspension, the link is an elongated leaf element, the first point being located at a first end of the elongated leaf element, the second point being located somewhere on the longitudinal extent of the elongated leaf element, and the third point being located at the second end of the elongated leaf element. The link thereby works as a compliant link with an intermediate fulcrum point connected to the chassis.
Correspondingly, in a second preferred embodiment of the vehicle suspension, the first, second and third points each have a fixed position at the link. Accordingly, a constrained link guiding the wheel carrier relative to the chassis is provided.
In a third preferred embodiment of the vehicle suspension, the suspension includes a second link, the second link being pivotally connected at one of its ends to the wheel carrier, and being pivotally connected at its second end to the rigid chassis. In particular, the second link advantageously is rigid and is the lower arm of a respective parallelogram, the parallelogram guiding the wheel carrier relative to the chassis. In addition, this link according to the invention is advantageously the upper lateral arm of the parallelogram. Furthermore, it is also preferred to replace the lower arm with a similarly constrained compliant link.
Accordingly, in a forth preferred embodiment of the vehicle suspension, the links are part of a parallelogram guiding the wheel carrier relative to the chassis, the elastic link being the upper lateral arm of the parallelogram, and the second link being rigid and being the lower arm of the parallelogram. In one embodiment of such a vehicle suspension, the elastic link replaces the suspension's upper arm and coil spring with a single, ternary supported compliant link. The ternary link is thereby defined as a link with three pin-joint connections to it. The link is pin-joined to the wheel carrier at the one end, and pin-joined to the chassis at the fulcrum. The other end of the link is pin-joined to the shackle attached to the chassis. The shackle allows for effective length changes of the elastic link as it bends. The distance from the fulcrum to the wheel carrier joint primarily affects the kinematic behavior of the wheel during bounce and rebound of the link, while the entire length of the elastic link is available for energy storage in the form of elastic strain energy in bending.
In a fifth preferred embodiment of the vehicle suspension, the second point includes two bumps fixed at the link, at least one suspension element holding the link by carrying it between the two bumps.
In an alternative sixth preferred embodiment of the vehicle suspension, the second point includes one single bump being fixed at the link, at least one suspension element holding the link by encompassing the bump.
In an alternative seventh preferred embodiment of the vehicle suspension, the second point includes at least one suspension element, the suspension element clamping the link.
Finally, in an eighth preferred embodiment of the vehicle suspension, a fixation of the second point at the rigid chassis is provided, the fixation being displaceable at the rigid chassis.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.